A Review on “Dry Syrups for Paediatrics”

Abstract

Suspensions may be defined as preparations containing finely divided drug particles (the suspensoid) distributed somewhat uniformly throughout a vehicle with or without stabilizers and other additives in which drug exhibits a minimum degree of solubility hence conventional oral suspension can be administered immediately (ready to use form) and not requiring reconstitution at the time of dispensing are simply designated as "Oral Suspension".There is an important category of suspension that are available as dry powders intended for suspension in liquid vehicles. These are dry mixtures containing the drug and suitable suspending and dispersing agents to be diluted and agitated with a specific quantity of vehicle, most often purified water. Drugs that are instable if maintained for extended periods in the presence of aqueous vehicle (eg., many antibiotic drugs) are frequently supplied as dry powder mixtures for reconstitution at the time of dispensing. This type of preparation is designated in the USP by a title "for Oral Suspension". The reconstituted system is the formulation of choice when the drug stability is a major concern. After reconstitution, these systems have a short but acceptable life if stored at refrigerator temperatures. Reconstitutable oral systems show the adequate chemical stability of the drug during shelf life, avoids the physical stability problems related to solubility, pH and incompatibilities with other ingredients and also reduce the weight of the final product because the aqueous vehicle is absent and consequently the transportation expenses may be reduced .Dry syrup form of the drug is also useful in case of bioavailability as it has high bioavailability rather than tablets and capsules as it disintegrates in water outside of the oral cavity and directly the suspension is gone through the gastrointestinal tract. So the suspension easily absorbs in the GIT.A number of commercial and official preparations are available as dry powder mixtures. The present review gives an account of the excipients used, methods of preparation of dry syrups along with their evaluations, their packaging, examples of research articles, few marketed preparations.

Dry syrup: An overview

“…Final product must have an acceptable appearance, odor and taste. Reasons for formulation of such suspensions [16] Reconstitute suspension is formulated due many reasons such as for patient which have difficulty in swallowing, drug stability etc. Some reasons are discussed below.…”

“…Suitable for insoluble or poorly soluble API. Excipients used [3,16] Number of excipients should be minimum as more the number of excipients in the formulation, the greater is the possibility of problems, for example, the chances of compatibility problems are increased as more excipients are used. More processing is required to incorporate more excipients.…”

“…Eg.Polysorbate 80, Sodium lauryl sulfate. Other excipients [16] The other excipients include buffers, preservatives, flavors and colors. Buffers are used to maintain the optimal pH for all excipients.…”

“…Combination product [14,16,18] Powdered and granulated excipients can be combined to overcome some disadvantages of granulated products. Less energy and equipment for granulation may be required if the majority of the diluents can be added after granulation.…”

“…(6) Particle size: The oral reconstitutable suspension is evaluated, the average particle size of the formulation is examined using standard microscopy method average and standard deviations of 100 particles are estimated. Packaging and storage [16] Dry powder for reconstitution packaged in wide mouth container or in sachet in case of unit dosing. 1.…”